Environmental controls on African herbivore responses to landscapes of fear (2021) Davies et al., Oikos. https://doi: 10.1111/oik.07559
Image Credit: Olga Ernst, CC BY-SA 4.0, Image Cropped
Despite the incredible variation seen in nature when it comes to flora and fauna, it always seems like the two types that most people know are predators and prey. Prey animals being those that eat plants (or other animals), and the predators being those that eat those prey animals. Because prey animals must not only eat food, but try to avoid becoming food for something else, they must always be on the lookout. This watchfulness and awareness is what creates a “landscape of fear” (See Did You Know?), but variation is inherent to the natural world, and there are likely many things that prey animals consider when they pick where they decide to forage. Today’s authors wanted to investigate what factors influence the prey animals choice of foraging areas, and if that selection varies with the environment during the dry season when there isn’t much food available.
Image Credit: pxfuel, CC0 1.0, Image Cropped
Monitoring the silver carp invasion in Africa: a case study using environmental DNA (eDNA) in dangerous watersheds (2020) Crookes et al., NeoBiota, http://doi.org/10.3897/neobiota.56.47475
One thing the last two months have taught us all is that testing for a problem is crucial. The earlier you catch a problem, the more of a chance you have to stop that problem spreading. Coronavirus is one example, invasive species is another. Detecting an invader arriving early on means you can potentially remove it before it has become properly established, saving millions of dollars down the line.
But often testing isn’t practical. Take freshwater environments. Sometimes a river may be hard to get to. Sometimes it may be infested with crocodiles and hippos. Makes regular testing methods like electrofishing or gillnetting a bit tricky.
Image Credit: Kevin Pluck, CC BY 2.0, Image Cropped
Brain expansion in early hominins predicts carnivore extinctions in East Africa (2020) Faurby et al, Ecology Letters, https://doi.org/10.1111/ele.13451
We’ve covered humans and their harmful effects many times here on Ecology for the Masses (see my recent breakdown from last month). Despite all of the colorful examples of our current effects on the wildlife of our planet, a significant amount of research has implicated Homo sapiens as the driver of the extinction of some of the megafauna of the prehistoric world, events that happens millions of years ago. Another possibility is that we as organisms (hominins, not Homo sapiens specifically) have been impacting other species for a very, very long time.
Today, East Africa is home to the most diverse group of large carnivores on the planet (though it is still less diverse than what was once seen in North America and Eurasia). Millions of years ago East Africa had an even more diverse assemblage of large carnivores, including bears, dogs, giant otters, and saber-toothed cats. The change in climate since that time may have caused the decline in large carnivore diversity, but another explanation is the rise of early hominins (our ancestors). Using fossil data, the authors of today’s paper wanted to figure out if it was indeed early hominins that drove many large carnivores extinct.